The most common birth defects in the world are unfortunately some of the most dangerous to babies. Congenital heart defects affect about 40,000 babies in the U.S. and Canada. The procedures to repair heart defects can range from simple to incredibly complex and potentially dangerous. However, Toronto’s Hospital for Sick Children has an idea for how to practice delicate heart surgeries before opening up a baby’s chest.

Heart surgeons in Toronto are preparing for these complicated surgeries with exact replicas of tiny hearts with a 3D printer.

3D-printed hearts: How do they work?

With 3D-printed hearts, surgeons can practice on an exact replica of the organ they’re preparing for without ever opening the baby’s chest. Doctors take detailed scans of the tiny hearts that essentially creates a blueprint that they can feed to a 3D printer. Adding plastic layer upon layer, the printer builds an exact replica of the organ. This allows surgeons to develop strategies for surgery and practice the maneuvers until they’re ready for the operation.

There is one drawback, however. Along with the successes comes the steep costs of 3D models. Each replica costs about $500, and doctors usually practice on several models before surgery. However, as technology evolves, health care professionals expect these models to cost considerably less in the coming years.

Mortality rate greatly reduced

Toronto’s Hospital for Sick Children has a far lower mortality rate than those of hospitals across North America and Europe. Using 3D models before entering the operating room has helped greatly lower deaths for two types of heart surgeries: arterial switch and ventricular septal defects. The mortality rate for these operations are 3.2 percent in North America and 6.2 percent in Europe. The mortality at this Toronto hospital? 1.7 percent.

Practice makes perfect

Without 3D-printed models, doctors have no choice but to practice heart surgeries on babies. As Dr. Glen Van Arsdell, the head of cardiovascular surgery, said to CTV News, “I had to learn practicing on babies. Think about how much better it will be for future generations if we can have those surgeons learn how to operate on models instead of on babies.”